Hi when I disconect the autopilot for landing I can't turn off the alarm. How can I resolve?

How do you turn off the autopilot? Do not use the bar on the MCP. You have to wait 1.5 seconds, and then hit your A/P disc button again. An A/P disc clickspot is on the "TOGA-screw" on the MCP

You need to have the resettable alarm option checked in the aircraft-specific options in PMDG settings.

The default FSX button "Z" is an Autopilot toggle.

If you press Z once, the Autopilot turns on. A second press turns it off. A third press turns it on again. This is not what you want to use for the PMDG 777.

 

The default Ctrl+Shift+Z button is the keypress to "Disconnect Autopilot"

One press of Ctrl+Shift+Z disconnects the autopilot

A second press of Ctrl+Shift+Z disconnects the autopilot

A third press of Ctrl+Shift+Z disconnects the autopilot

 

That means if you press this combination once, the autopilot of the 777 will switch off and the wailer horn will sound.

A second press, 1.5 seconds later will cause the wailer horn to switch off (and the autopilot is already off so nothing further happens there).

 

The other option is to right click the invisible clickspot that makes Takeoff Thrust engage when left clicked. Wait 1.5 seconds. and right click the same spot a second time.

 

The real 777 needs 2 clicks of the disconnect button too. One to switch off autopilot control, and a second one 1.5 seconds later to silence the alarm.

 

My suggestion is to set up a button on your joystick/yoke to be the equivalent of Ctrl+Shift+Z.

 

Finally:

http://lmgtfy.com/?q=PMDG+777+autopilot+sound

For what it's worth, the introduction manual is pretty short and contains an entire section explaining most of the things that would trip you up, and what to do.

Thank you for answer me